Not One, Not Two, But at Least Three: Activity Origin of Copper Single-Atom Catalysts toward CO₂/CO Electroreduction to C₂₊ Products

Abstract

Copper (Cu) single-atom catalysts (SACs) exhibit great potential for generating multicarbon (C 2+ ) products, but the intrinsic activity of single-atom Cu (Cu 1 ) under realistic conditions remains controversial. Herein, we perform extensive calculations with explicit solvation to investigate the underlying mechanism of Cu SACs, disclosing the absence of C 2+ activity in Cu 1 sites regardless of the different substrates. The original Cu 1 sites (first taking Cu 1 stably anchored on carbon nitride as an example) cannot facilitate *CO hydrogenation and CO−CO coupling due to the lack of active sites nearby, and they are unstable under operation, causing leaching and aggregation to form small Cu clusters. The derived Cu clusters composed of at least three Cu atoms can efficiently promote CO−CO coupling, as revealed by kinetic analyses. We extend the modeling to other typical Cu SACs and reveal that all of the Cu 1 sites are inactive, while the C 2+ performance of the derived Cu-cluster catalysts is substrate-dependent. This study offers mechanistic insights into Cu SACs and provides practical guidance for their rational optimization.

Reaction Mechanism of Rapid CO Electroreduction to Propylene and Cyclopropane (C3+) over Triple Atom Catalysts

“…The concept of multiatom catalysts such as triple atom catalysts (TACs) has begun to provide more opportunities for complex electrochemical reactions. − For example, the TAC combination of three metal atoms that are atomically dispersed on a support such as nitrogen-doped Graphene or g-C 3 N 4 to form a random-shape structure ,, or a triangular structure. − TACs may be beneficial through either orbital coupling or nonbonding interaction of metal atoms to participate in electrochemical reactions toward N–N and O–O bond dissociation or C–C coupling . For example, a triangular Ru3-TAC on nitrogen-doped carbon was experimentally synthesized and shown to be efficient for the oxidation of alcohols .…”

Machine Learning Big Data Set Analysis Reveals C–C Electro-Coupling Mechanism

“…Theoretical research offers the capabilities to address this problem from a global perspective by simultaneously considering the complete reaction network and active site composition within the same system, thereby providing valuable guidance for experiments. Recent experimental , and theoretical studies have shown that the triatom clusters form as active structure for C–C coupling under CO 2 reduction working conditions. Consequently, by constructing reaction networks and engineering active-site compositions − based on this structure, a comprehensive big data set can be established to analyze the underlying mechanisms in depth.…”